Method for making and maintaining an impression of the shape of an object



- z .June 7,'1949. A 'WINE/ID 2,472,754 METHOD FOR MAKINGAND'MAINTAINING AN IMPRESSION OF THE SHAPE OF O CTS Y Filed 0ct. 20, 5

Patented June 7, 1949 UNITED STATES PATENT DCF-.KOI

OFFICE METHOD FOR MAKING AND MAINTAIN- ING AN IMPRESSION OF THE SHAPE OFAN OBJECT 4 claims. 1

This invention relates to a method for making and maintaining animpression of the shape of an object, and although it is not limited inits application to making the impression of any particular object, it iswell adapted and particularly intended for use in making an impressionof the shape of a human foot. For the purpose of illustration, and notof limitation, the invention will therefore be described as applied tothat use.

In the making of a shoe to t an individual human foot, which maysometimes be an abnormally or peculiarly shaped foot, difficulty isexperienced in fashioning a special shoe last on which a shoe can bebuilt that will satisfactorily conform to the shape and dimensions ofthe foot.

In carrying out the invention, use is made of the broad principle setforth in my application Serial No.`555,010, filed Se tember 20 1944. Thepresent invent1on makes it possible easTTto obtain a ilrm and faithfulimpression of the shape of a foot (or other object) in a closed orpartially closed cavity of such shape that the object making theimpression could not be Withdrawn from an ordinary mold.

In the accompanying drawings which illustrate the invention as appliedto making an impression of a human foot,

Fig. 1 is a cross-section of the device;

Fig. 2 is a longitudinal section of the device;

Fig. 3 is a plan view of the device;

Fig. 4 is a plan view of the deformable unit used in the bottom of thedevice;

Fig. 5 is a plan view of one of the other deformable units and Fig. 6 isa fragmentary vertical section similar to Fig. 2 but showing the step ofpreparing a molded replica of the foot illustrated in Fig. 2.

The casing I is a box-like structure which may be of any size and shapeappropriate to the size and shape of the object to be copied. It isshown in the drawings as an oblong structure having bottom, side and endwalls and an open top through which the foot and the deformable unitsmay be inserted and removed.

Laid in the bottom of the casing l and substantially filling the lowerpart of the casing is a deformable impression receiving unit 2,consisting of a sack 3' of sheet rubber or other thin, tough, flexibleand extensible material filled with a mass l of granular material, suchas sand, mixed with fluid, such as air or water, in such quantity thatthe mixture as a whole is suillciently mobile to receive an impressionof the object, in this case a foot, when pressed into the unit.

The foot 5, shown in rear view in Fig. 1 and in side view in Fig. 2, isthen placed upon the top of the sack 3 and pressed into the deformableunit 2 under such weight as is desired, preferably under the full weightwhich the foot normally carries in order to obtain an impression of theshape of the foot under load as in use, which differs from the shape ofa passive foot.

Additional deformable impression receiving units 6, Fig. 5, are providedofsuch size and shape as to be adaptable to the object, in this examplea human foot, and to the casing. Otherwise, each such additional unithas the same characteristics as the above described unit 2 in that itcomprises a sack or container 1 filled with a mobile mixture 8 ofgranular material and fluid.

After the foot has been pressed into the deformable bottom unit 2 andproperly seated to form the impression, additional deformable units areclosely packed about the foot so that the assembled units will envelopand conform to the shape of the foot and form within the assemblage apartially closed cavity (open only at 9, Fig. 3, about the ankle) shapedlike the foot. Two such additional units are shown in the drawings, oneplaced at each side and overlapping the top of the foot. It will beunderstood that the assemblage may consist of as many such units as arenecessary or desirable to envelop the particular object or part of theobject of which the impression is to be made.

Each deformable unit is provided with a nipple I0 communicating with theinterior of the container sack and sealed thereto in any ordinarymanner. The inner terminal of the nipple is preferably screened asindicated at Il, Fig. 2, to prevent the escape of granular materialwhile permitting the passage of fluid. Each nipple is also provided witha cock or hand valve I2 to open or close the passage through the nipple.

When the assembled deformable units have been properly packed about theobject so that the desired impression of the object has been formedwithin the assemblage, the fluid pressure within each unit is reduced byexhausting fluid from the mixed mass of granular material and fluid toan extent suillcient to solidify the granular mass by virtue of theprinciples more fully explained in my said application Serial No.555,010. Any suitable form of exhaust pumping device may be used forreducing the fluid pressure, that shown in the drawing being aconventional air pump, indicated at P, connected-,to one of the nipplesby a. flexible tube. The pump may ril"- desirably be a pressure-vacuumpump which may be used not only to exhaust fluid for solidifying thegranular mass, but also to force fluid into the sack in such quantity asmay be desirable to loosen the grains and render the mixturesufficiently mobile to receive the impression of the object.

After each unit has been solidified and the partial vacuum in each hasbeen sealed by its valve I2, the entire assemblage forms in effect asolid mold of built-up interiltting units having an interior cavityconforming to the shape of the object.

In order to remove the foot, as many of the solidified units are removedas may be necessary to permit the foot to be withdrawn, after which theunits are replaced in their original positions so as to restore thecomplete impression left by the foot. To facilitate such removal in .theexample illustrated by the drawings, one or both side walls of thecasing I may be hinged as indicated at I3. By swinging the hinged sidedownwardly and away from the assembly, one of the upper units, nowsolidified, may be easily removed, and the foot may be withdrawn sdewisewithout disturbing the other units, after which the removed unit may bereplaced and the hinged side of the casing closed and locked to hold theassemblage against disarrangement. An outline of the cavity left in theassembled unit by the foot is indicated in plan view in Fig. 3 at I4.

A casting may now be made of the mold cavity within the assemblage bymeans of a suitable plastic material and used as a pattern forfabricating a shoe last appropriate to the individual foot which formedthe impression; or a pattern of the interior cavity may be made byinserting a sack ll of flexible, extensible and impervious sheetmaterial into the cavity, inflating the sack to make it conform to theshape of the cavity, lling the sack with a mixed mass of granularmaterial and fluid and solidifying the granular mass by exhausting thefluid through a nipple I', all as more fully explained in my saidapplication Serial No. 555,010 and illustrated in Fig. 6 thereof.Obviously, if a pattern is desired somewhat larger than the foot butfollowing its contour, this could be obtained by making the impressionfrom a foot wearing a sock to enlarge the dimensions of the impressionto an extent depending on the thickness of the material of the sock.

A single deformable unit such as 2 disposed in a shallow casing willserve a useful purpose in assisting a retail shoe salesman to flt a shoeto a customers foot. An impression of the outline of the foot may bemade by the customer and solidifled in the manner already described, andthen by taking measurements of the impression and observing its shapeand style, the salesman will be in a position to recommend the size andstyle of shoe most appropriate for the particular customer.

The invention is adaptable to a great variety of other objects as wellas a foot and may be practiced and embodied in many forms and the scopeof the invention is not to be limited excepting as defined in thefollowing claims.

I claim:

1. The method of making and maintaining an impression of the shape of anobject by means of a plurality of deformable, impression receivingunits, each unit comprising a container wall of flexible, extensible andimpervious sheet material lled with a deformable mass of mixed granularmaterial and fluid, which method comprises packing a number of saiddeformable units about the object so that the assembled units willenvelop and conform to that surface of the object which is to beduplicated, solidifying the granular mass in each unit by reducing thepressure of the fluid therein, and removing the object from thesolidified units.

2. The method of making and maintaining an impression of the shape of anobject by means of a plurality of deformable, impression receivingunits, each unit comprising a container wall of flexible, extensible andimpervious sheet material filled with a deformable mass of mixedgranular material and fluid, which method comprises packing a number ofsaid deformable units about the object so that the assembled units willenvelop and conform to that surface of the object which is to beduplicated, solidifying the granular mass in each unit by reducing thepressure of the fluid therein, removing certain of the solidifled unitsfrom the assembly to facilitate removal of the object, removing theobject, and then replacing the removed unit or units to restore thecomplete impression left by the object.

3. The method of making and maintaining an impression of the shape of anobject by means of a plurality of deformable, impression receivingunits, each unit comprising a container wall of flexible, extensible andimpervious sheet mate-` rial filled with a deformable mass of mixedgranular material and fluid, which method comprises packing a number ofsaid deformable units about the object so that the assembled units willenvelop and conform to that surface of the object which is to beduplicated, solidifying the granular mass in each unit by reducing thepressure of the fluid therein, removing the object from the 1 solidifiedunits, lling the cavity with material capable of conforming to thecontour of the cavity, solidifying said material and removing it fromthe solidied units.

4. The method of making and maintaining an impression of the shape of anobject by means of a plurality of deformable, impression receivingunits, each unit comprising a container wall of flexible, extensible andimpervious sheet material lled with a deformable mass of mixed granularmaterial and fluid, which method comprises packing a number of saiddeformable units about the object so that the assembled units willenvelop and conform to that surface of the object which is to beduplicated, solidifying the granular mass in each unit by reducing thepressure of the fluid therein, removing the object from the solidifiedunits, inserting a sack of flexible,

. extensible and impervious sheet material into the cavity left by theobject, inflating the sack to cause it to conform with the surface ofthe cavity, filling the sack with granular material whose interstitialspaces are fllled with fluid, and solidifying the granular mass withinthe sack by reducing the pressure of the fluid.

WARREN J. MEAD.

REFERENCES CITED 'I'he following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,675,517 Scholl July 3, 19282,145,941 Maxfield Feb. 7, 1939 2,256,036 Redmond Sept. 16, 19412,277,288 Berch Mar. 24, 1942

